Bleaching fats and oils.



rnmmuo Mt'rLLEn, or LonWIGsHarnN-oN-rHn-nmun GERMANY, ASSIGNOR 1'0BADISUAE ANILIN & SODA FABRIK, 0F

MANY, A oozaroaa'rrom.

LUDWIGSHAFEN-OILTHE-BHINE, GER- BLEACHIN G FATS AND OILS.

No Drawing.

To all whom it may concern:

Be it known that I, F mansion MULnnn, a subject of the King of Prussia,residing at Ludwigshafen-on-the-Rhine, Germany,

have invented new and useful improvements in Bleaching Fats and Oils, ofwhich the following is a specification.

The usual method of bleaching o1 ls and fats of animal and vegetableorigin has chiefly consisted in treating them With animal charcoal or infiltering them through fuller-s earth. These processes are expensive andentail loss of material.

I have found that animal and vegetable fatty oils can be very Wellbleached by treating them in the presence of an alkaline reagent, andpreferably While hot, with solutions of hydrosulfites or of theircompounds with aldehydes, ketones, etc., or of the correspondingsulfoxylates. For the purpose of this invention compounds ofhydrosulfites with aldchydes, ketones, etc, and the correspondingsulfoxylates are equivalent to hydrosulfites. The alkali first of allcombines with the free fatty acid," which is always present in the crudefats, and then, in some cases, with a part of the fat itself, formingsoap. The soap enables the aqueous hydrosulfite solution to mixintimately with the fat, and the excellent bleaching action is due toits presence. Hence it is equivalent to replace the alkali or a partthereof from the commencement by soap. The re action can be carried outeither by first of all adding the alkali to the fat and subsequently thehydrosulfite, or the two components can be simultaneously added, forinstance, in the form of an alkaline hydrosulfite solutionr After theoil has been bleached, it is allowed to settle and is then separatedfrom the soapy solution and Washed.

The following example will serve to illus- S pecification of LettersPatent.

Application filed February 20, 1912.

Patented Mar. 3, 1914. Serial No. 678,879.

trate further the nature of my invention, which, however, is notconfined to this example. containing 3% free fatty acid, are placed in avessel provided with a stirrer and heated to about 100 C. by means ofdirect steam, and a quantity of water is added to make up the totalquantity of Water present to about 100 liters. To the hot mixture of oiland Water a solution is slowly added of 14 liters of caustic sodasolution of -10 Be. and 1 kilo of sodium hydrosulfite in about 100liters of water. The mixture is heated. While stirring, for aboutanother 30 minutes, then allowed to settle, the soap solution whichsettles on the bottom of the vessel is drawn off and the last traces ofsoap are removed by repeated Washing with Water. The process can beWorked in a similar manner When replacing the sodium hydrosulfite by anequal quantity of sodium formaldehyde sulfoxylate, or of sodiumformaldehyde hydrosulfite. prepared, for instance, from 1 kilo of sodiumhydrosulfite, 14 liters of caustic soda solution of 4-0"- 136., 750cubic centimeters of 40 formaldehyde solution, and 100 liters of Water.

Now What I claim is 1. The process of bleaching fats and oils ofvegetableand animal origin by treating the same with solutions ofhydrosulfites in the presence of alkaline reag nts.

2. The process of bleaching fats and oils of vegetable and animal originby treating them with an alkaline solution of sodium hydrosulfite.

In testimony whereof l have hereunto set my hand in the presence of twosubscribing Witnesses.

FRIEDRICH MULLER. Witnesses:

' J. ALno. LDOYD,

A. C. Trr'rMANNj Copier of this patent may be obtained for five centseach, by addressing the Commissioner 01' Patents.

Washington, D. 0."

1,000 kilos of crude cocoanut oil,

